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प्रश्न
A zener diode is fabricated by heavily doping both p- and n- sides of the junction. Explain, why?
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उत्तर
It is a heavily doped p-n junction. As a result, the depletion region formed is very thin and the electric field of the junction is extremely high even for a small reverse bias voltage.
The I-V characteristics of a Zener diode are shown in the figure below:
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संबंधित प्रश्न
In a p-n junction diode, the current I can be expressed as
I = `"I"_0 exp ("eV"/(2"k"_"BT") - 1)`
where I0 is called the reverse saturation current, V is the voltage across the diode and is positive for forward bias and negative for reverse bias, and I is the current through the diode, kBis the Boltzmann constant (8.6×10−5 eV/K) and T is the absolute temperature. If for a given diode I0 = 5 × 10−12 A and T = 300 K, then
(a) What will be the forward current at a forward voltage of 0.6 V?
(b) What will be the increase in the current if the voltage across the diode is increased to 0.7 V?
(c) What is the dynamic resistance?
(d) What will be the current if reverse bias voltage changes from 1 V to 2 V?
Explain briefly with the help of necessary diagrams, the reverse biasing of a p-n junction diode. Also draw characteristic curves.
Draw a circuit diagram to study the input and output characteristics of an n-p-n transistor in its common emitter configuration. Draw the typical input and output characteristics.
The drift current in a reverse-biased p-n junction is increased in magnitude if the temperature of the junction is increased. Explain this on the basis of creation of hole-electron pairs.
In a p-n junction with open ends,
(a) there is no systematic motion of charge carries
(b) holes and conduction electrons systematically go from the p-side to n-side and from the n-side to p-side respectively
(c) there is no net charge transfer between the two sides
(d) there is a constant electric field near the junction.
Find the current through the battery in each of the circuits shown in figure.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
Find the equivalent resistance of the network shown in figure between the points A and B.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
A load resistor of 2kΩ is connected in the collector branch of an amplifier circuit using a transistor in common-emitter mode. The current gain β = 50. The input resistance of the transistor is 0.50 kΩ. If the input current is changed by 50µA. (a) by what amount does the output voltage change, (b) by what amount does the input voltage change and (c) what is the power gain?
During the formation of a p-n junction ______.
In p-n junction diode ______.
